ABSTRACT. Approximately half of all 14-17 years olds in the U.S. are estimated to be victims of physical assault; chronic stress and trauma exposure are particularly prevalent for youth growing up in high-crime urban communities. Emotion regulation difficulties due to stress and trauma exposure contribute to disparities in mental health problems and school failure, with low-income and African American youth at much higher risk than their higher-income, White counterparts. Schools serving high-crime communities, however, do not offer universal trauma-informed strategies to support student success. RAP Club is a school-based group prevention program aimed at improving emotion regulation and decision-making in urban upper middle school students to improve their transition to high school. The program fills key gaps in current school practices, including a trauma-informed approach, universal delivery to all students without pre-screening, transdiagnostic effects on internalizing problems as well as behavioral issues, and a focus on upper middle school students. Our team adapted RAP Club from Structured Psychotherapy for Adolescents Responding to Chronic Stress (SPARCS), a group treatment for adolescents based on empirically supported mindfulness and cognitive- behavioral techniques. Using a novel delivery method, RAP Club is co-facilitated by school mental health personnel and young adult community members to promote student engagement. In our NIMH-funded pilot research, the program improved classroom behavior, social functioning, and academic competence. The program improved outcomes for students at varying levels of baseline distress?even low levels?suggesting its appropriateness as a universal model. Building on that work, the proposed R01 trial will test whether urban eighth grade students randomly assigned to RAP Club show improved emotional, behavioral, and academic outcomes in eighth and ninth grades compared to those assigned to Healthy Topics, a health education control group. Intervention and control programs will each be delivered by different school personnel with co- facilitation by young adult community members. The research will be conducted in 32 Baltimore City Public Schools serving urban communities with high rates of violence exposure. We will collect teacher- and student- reported data on student self-regulation, emotional functioning, classroom behavior, and academic performance at pre- and post-intervention and 4-month follow up, as well as student data at 12-month follow up. We will gather school record data on academic indicators in the year before, year of, and year following study participation. We will evaluate factors relevant to program implementation and potential sustainability, including stakeholder perspectives and cost data. The RAP Club model of trauma-informed, universal support has potential for widespread dissemination in school districts serving disadvantaged youth nationwide.